PinEntryEditText.java

import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.ColorStateList;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.os.Build;
import android.text.Editable;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.view.ActionMode;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.EditText;

public class PinEntryEditText extends EditText {
    public static final String XML_NAMESPACE_ANDROID = "http://schemas.android.com/apk/res/android";

    private float mSpace = 24; //24 dp by default, space between the lines
    private float mCharSize;
    private float mNumChars = 4;
    private float mLineSpacing = 8; //8dp by default, height of the text from our lines
    private int mMaxLength = 4;

    private OnClickListener mClickListener;

    private float mLineStroke = 1; //1dp by default
    private float mLineStrokeSelected = 2; //2dp by default
    private Paint mLinesPaint;
    int[][] mStates = new int[][]{
            new int[]{android.R.attr.state_selected}, // selected
            new int[]{android.R.attr.state_focused}, // focused
            new int[]{-android.R.attr.state_focused}, // unfocused
    };

    int[] mColors = new int[]{
            Color.GREEN,
            Color.BLACK,
            Color.GRAY
    };

    ColorStateList mColorStates = new ColorStateList(mStates, mColors);

    public PinEntryEditText(Context context) {
        super(context);
    }

    public PinEntryEditText(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context, attrs);
    }

    public PinEntryEditText(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(context, attrs);
    }

    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
    public PinEntryEditText(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
        init(context, attrs);
    }

    private void init(Context context, AttributeSet attrs) {
        float multi = context.getResources().getDisplayMetrics().density;
        mLineStroke = multi * mLineStroke;
        mLineStrokeSelected = multi * mLineStrokeSelected;
        mLinesPaint = new Paint(getPaint());
        mLinesPaint.setStrokeWidth(mLineStroke);
        if (!isInEditMode()) {
            TypedValue outValue = new TypedValue();
            context.getTheme().resolveAttribute(R.attr.colorControlActivated,
                    outValue, true);
            final int colorActivated = outValue.data;
            mColors[0] = colorActivated;

            context.getTheme().resolveAttribute(R.attr.colorPrimaryDark,
                    outValue, true);
            final int colorDark = outValue.data;
            mColors[1] = colorDark;

            context.getTheme().resolveAttribute(R.attr.colorControlHighlight,
                    outValue, true);
            final int colorHighlight = outValue.data;
            mColors[2] = colorHighlight;
        }
        setBackgroundResource(0);
        mSpace = multi * mSpace; //convert to pixels for our density
        mLineSpacing = multi * mLineSpacing; //convert to pixels for our density
        mMaxLength = attrs.getAttributeIntValue(XML_NAMESPACE_ANDROID, "maxLength", 4);
        mNumChars = mMaxLength;

        //Disable copy paste
        super.setCustomSelectionActionModeCallback(new ActionMode.Callback() {
            public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
                return false;
            }

            public void onDestroyActionMode(ActionMode mode) {
            }

            public boolean onCreateActionMode(ActionMode mode, Menu menu) {
                return false;
            }

            public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
                return false;
            }
        });
        // When tapped, move cursor to end of text.
        super.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                setSelection(getText().length());
                if (mClickListener != null) {
                    mClickListener.onClick(v);
                }
            }
        });

    }

    @Override
    public void setOnClickListener(OnClickListener l) {
        mClickListener = l;
    }

    @Override
    public void setCustomSelectionActionModeCallback(ActionMode.Callback actionModeCallback) {
        throw new RuntimeException("setCustomSelectionActionModeCallback() not supported.");
    }

    @Override
    protected void onDraw(Canvas canvas) {
        //super.onDraw(canvas);
        int availableWidth = getWidth() - getPaddingRight() - getPaddingLeft();
        if (mSpace < 0) {
            mCharSize = (availableWidth / (mNumChars * 2 - 1));
        } else {
            mCharSize = (availableWidth - (mSpace * (mNumChars - 1))) / mNumChars;
        }

        int startX = getPaddingLeft();
        int bottom = getHeight() - getPaddingBottom();

        //Text Width
        Editable text = getText();
        int textLength = text.length();
        float[] textWidths = new float[textLength];
        getPaint().getTextWidths(getText(), 0, textLength, textWidths);

        for (int i = 0; i < mNumChars; i++) {
            updateColorForLines(i == textLength);
            canvas.drawLine(startX, bottom, startX + mCharSize, bottom, mLinesPaint);

            if (getText().length() > i) {
                float middle = startX + mCharSize / 2;
                canvas.drawText(text, i, i + 1, middle - textWidths[0] / 2, bottom - mLineSpacing, getPaint());
            }

            if (mSpace < 0) {
                startX += mCharSize * 2;
            } else {
                startX += mCharSize + mSpace;
            }
        }
    }


    private int getColorForState(int... states) {
        return mColorStates.getColorForState(states, Color.GRAY);
    }

    /**
     * @param next Is the current char the next character to be input?
     */
    private void updateColorForLines(boolean next) {
        if (isFocused()) {
            mLinesPaint.setStrokeWidth(mLineStrokeSelected);
            mLinesPaint.setColor(getColorForState(android.R.attr.state_focused));
            if (next) {
                mLinesPaint.setColor(getColorForState(android.R.attr.state_selected));
            }
        } else {
            mLinesPaint.setStrokeWidth(mLineStroke);
            mLinesPaint.setColor(getColorForState(-android.R.attr.state_focused));
        }
    }
}

PinEntryLayout.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:clipChildren="false"
    android:clipToPadding="false"
    android:orientation="vertical"
    android:padding="@dimen/activity_horizontal_margin"
    tools:context="com.alimuzaffar.customwidgets.MainActivity">

    <TextView
        android:textAppearance="@android:style/TextAppearance.Large"
        android:text="Please enter PIN"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

    <com.alimuzaffar.customwidgets.PinEntryEditText
        android:id="@+id/txt_pin_entry"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:cursorVisible="false"
        android:digits="1234567890"
        android:inputType="number"
        android:maxLength="4"
        android:textIsSelectable="false"
        android:textSize="20sp" />

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="32dp"
        android:hint="Regular EditText"/>

</LinearLayout>

PinEntryTestActivity.java

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        final PinEntryEditText txtPinEntry = (PinEntryEditText) findViewById(R.id.txt_pin_entry);
        txtPinEntry.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

            }

            @Override
            public void afterTextChanged(Editable s) {
                if (s.toString().equals("1234")) {
                    Toast.makeText(MainActivity.this, "Success", Toast.LENGTH_SHORT).show();
                } else if (s.length() == "1234".length()) {
                    Toast.makeText(MainActivity.this, "Incorrect", Toast.LENGTH_SHORT).show();
                    txtPinEntry.setText(null);
                }
            }
        });
    }
}

Excellent Job.
However, I am not being able to change the text color in PinEntryEditText.
I tried changing it from XML and progammatically thinking it would work as if it would work for EditText because the class is extending EditText class . But, I have had no luck with this? Is there any way to do so?

Excellent Job.
However, I am not being able to change the text color in PinEntryEditText.
I tried changing it from XML and progammatically thinking it would work as if it would work for EditText because the class is extending EditText class . But, I have had no luck with this? Is there any way to do so?

I am not able to change the text color? tried both in xml and programatically? please let me know how can be changed?

To change text color use getPaint().setColor(Color.parseColor("#FFFFFF")). You can write this on line 152.

there is error getting width of character
canvas.drawText(text, i, i + 1, middle - textWidths[0] / 2, bottom - mLineSpacing, getPaint());
should be
canvas.drawText(text, i, i + 1, middle - textWidths[i] / 2, bottom - mLineSpacing, getPaint());

for AndroidX extend androidx.appcompat.widget.AppCompatEditText instead of Edittext

--To change text color following this line write in PinEntryEditText.java class
To change text color use getPaint().setColor(Color.parseColor("#FFFFFF")). You can write this on line 152.
--To change edit text underline color to write following line in PinEntryEditText
Replace colorControlActivated, colorPrimaryDark, colorControlHighlight To "colorBackgroundFloating"

android:cursorVisible="true"
cursor is not visible.

How can change to a password edittext? Setting the attribute in XML or programmatically does not work

How can change to a password edittext? Setting the attribute in XML or programmatically does not work
what have you tried?

Have you tried
android:inputType="password"
?

i tried but its not working numbers are visible when input